This invention relates to wireless communication systems in general, more particularly, to improving system performance based on information derived from remotely operating mobile stations.
Wireless Communication systems, in general, and cellular systems, in particular, are extensively used to provide communication services to a wide array of mobile subscribers. For example, European Telecommunication Standard Institute (ETSI) has specified a Global Standard for Mobile Communication (GSM) that uses time division multiple access (TDMA) to communicate control, voice and text information over radio frequency (RF) channels. In the U.S., Telecommunication Industry Association (TIA) has published a number of Interim Standards, such as IS-136, that define various versions of digital advanced mobile phone service (D-AMPS), with the capability of transmitting voice and data to subscribers. Generally, these systems include scattered base stations that communicate via corresponding transceivers with mobile stations over uplink and down link RF channels. During normal operation, the base stations transmit communication signals to the mobile stations over downlink RF channels and receive communication signals from the mobile stations over uplink RF channels. Similarly, the mobile stations include transceivers that transmit communication signals over the uplink RF channels and receive communication signals over the downlink RF channels.
Over the years, communication system operators have recognized that quality of communication over RF channels is of utmost importance. The communication quality over the RF channels is affected by the condition of various radio elements, i.e., the antenna equipment and transceivers, of the base station. Therefore, system operators regularly monitor the operating condition of their systems, in order to offer their services with a satisfactory quality level. The regular monitoring of operating condition, which involves performing a battery of tests and measurements, is costly. As a result, the systems operators are constantly searching for ways to reduce their operating cost, without sacrificing the quality of the offered services.
Conventionally, test equipments, which are capable of establishing wireless communication with the base station for emulating communication path with mobile stations, are used to perform the test and measurements. Under one arrangement, a technician visits cell sites in order to perform manual measurements using the test equipment. The labor cost of performing the tests manually, however, is high, with such cost increasing as the size of a system and/or the number of its cell sites become larger. Therefore, less costly automated test and measurements methods are preferred, because they eliminate the need for visiting the cell sites, or, alternatively, such automated tests could allow the operator to more intelligently decide whether a site should be visited or not.
One conventional automated test method, known as Radio Frequency Test Loop (RFTL), provides a loop between the transmitter and receiver paths of a base station. In a test mode, RF switches, connected to suitable attenuators, couple the transmitter of the base station to its receiver to test base-station receiver and transmitter paths. The RFTL, however, provides for the testing of some but not all elements within the system. For example, the RFTL method does not include base station antenna and feeder in the test loop. As a result, if an external object, which is positioned near the base station, impedes propagation of RF waves to and from the base station, or if the antenna has been damaged, the RFTL method is unable to accurately detect reception quality.
In another conventional approach, disclosed in Patent number WO 97/33446 titled xe2x80x9cRemote Test of a Wireless Subscriber Connection,xe2x80x9d specific tests of an RF link and the test results are reported remotely from the mobile stations. Under this approach, a fixed number of test functions are pre-stored in the mobile station, for testing a particular link. In response to a test message, which is received via a radio path, the mobile station starts a specified test function and transmits the test results over the radio link. Sometimes, however, it is necessary to gather measurements at a particular geographical location in the network where testing is required. Furthermore, depending on operating conditions, a particular test measurement, not specified in the pre-stored test functions, may be necessary for the purpose of improving overall network performance and network configuration.
Therefore, the above described conventional methods do not offer the ability to automatically gather performance data relating to operational conditions of the mobile stations within one or more desired test locations. In particular, existing systems do not allow for configuring a mobile station for testing or evaluating an operational parameter not described or defined when the network was configured. Moreover, operational measurements performed by the mobile stations are limited to those specified by the operational software, for example, received signal strength (RSS) measurements. To gather specific operational data for a particular requirement, the operator must typically send out technicians into the field to take measurements using special test mobile stations or other equipment, which is an expensive and time-consuming activity.
Consequently, there exists a need to dynamically configure a mobile station to perform a specified test at one or more designated test locations, preferably using existing network elements, without manual intervention in the field.
The above stated need and other needs are addressed by a communication system that determines test locations for performing one or more specified tests. A radio network performance manager originates one or more executable mobile test software agents, to operate mobile stations within the system in a test mode. Preferably, the mobile test software agents represent addressable computer programs that can be transported across data networks for dynamically configuring the mobile stations to allow for collection of performance information. Based on location information within the communication system, such as those contained in location registers, a network controller identifies one or more mobile stations that are capable of executing mobile test software agents (MTSAs) at specified test locations. When executing the mobile test software agents, the MTSA-capable mobile stations switch their normal operating mode to a test mode. In this way, the radio network performance manager is provided with dynamically configured information that may be processed for improving system performance.
In the exemplary embodiment, once the MTSA-capable mobile stations are identified, a test message is transmitted from the network controller to determine the availability of MTSA-capable mobile stations for performing the tests. For example, the availability of the mobile stations may be determined based on a subscriber""s desire to participate in the test. Once available MTSA-capable mobile stations are identified, the MTSA is downloaded to the MSs and the tests are executed based on an execute message transmitted from the radio network performance manager.
According to some of the more detailed features of the present invention, in the test mode, the mobile stations may be configured to take specified measurements themselves or they may be configured to operate in a manner that measurements may be taken by one or more external resources. The measurements and the manner of operation may be dynamically configured by the mobile test software agent passing parameters relating to specified tests to the mobile stations. In this way, a mobile station may be configured to operate in the test mode under the control of the mobile test software agent, which, in an exemplary embodiment, is executed at the mobile station by a mobile resident application software.